Sliver drawing mechanism



Aug. 12, 1941.

E. E. BLAKE SLIVER DRAWING MECHANISM I Filed Oct. 29, 1956 .s Sheets-$heet 1 N TORJ 5am INVE ATTORNEY Aug. 12, 1941.. E. E. BLAKE SLIVERDRAWING MECHANISM 5 Sheets-Sheet. 2

Filed Oct. 29, 1936 I Aug. 12, 1941. j 'E, LAKE 5 Sheets-Shee t s FiledOct. 29, 1936 ATTORNEY Patented Aug. 12, 1941 UNITED STATES PATENTOFFICE SLIVER DRAWING MECHANISM Edmund E. Blake, Saco, Maine, assignor,bymesne assignments, to Saco-Loweli Shops,

Biddeford, Maine, a corporation of Maine Application October 29, 1936,Serial No. 108,191

2 Claims. (Cl. 19-133) This invention relates to drawing mechanisms ofthe general type used in the preparation of slivers for spinning. ,Whileit will be herein disclosed in connection with adrawing mechanismdesigned more especially for use in handling cotton slivers, it will beunderstood that the invention is equally applicable to operation onslivers or rovings composed of other fibers.

Such mechanisms perform the functions of drawing the slivers in order tostraighten the flbersand to dispose them in a more nearly parallelrelationship to each other, which is esthe trumpet moves in advance ofthe rolls until the end of the traverse is reached, and then it pauses,waits for the rolls to catch up with it, and starts in the oppositedirection ahead of the rolls. 'I'his necessarily involves complicationswhich are undesirable.

The present invention. satisfactorily deals with the conditions abovedescribed, and provides a sential in the best preparation of the sliverfor spinning. In addition, these mechanisms attenuate the sliver to asize suitable for the spinning operation. A long draft in a givenmachine is of advantage in producing the desired results Y with as fewoperations and as little handling of the fibers as possible. It has beenfound that such a draft is facilitated by folding the moving sliverlaterally upon itself at an intermediate point in the drawing operationand thus bringing the fibers at the selvages, which tend to-stray indrafting, back into the line of, flow of the main body of fibers beingdrafted and producing a sliver of approximately uniform cross-section.-

It has also been found that control of the fibers at the folding pointis improved by guiding the sliver through a trumpet as it is fed tothose :drawing rolls which precede the folding operation.

In operating a machine organized in accordance withthe foregoing, it wasfound that wear tended to become localized on the drawing rolls,articularly the covered top rolls, and this suggested the desirabilityof traversing; the silver with aview to distributing the wear.While'this normally is" a simple operation, it involves un usualproblems in a drawing mechanism of the character just described becauseof the factthat the sliver is in the form of a fiat ribbon from the timeit passes through the first pair of rolls until.

it reaches the folding rolls. In addition, the

drafting between any pairs of rolls is disturbed if, in any such zone,an attempt is made to move the ribbon laterally by forcing .amemberagainst the salvage ofthe ribbon. j V

A further diiiiculty found in attempting to traverse the sliver in anyorthodox fashion was that both thetrumpet and the folding rolls alsohadto be traversed, and in order to maintain thev sliver in properalinement with said rolls, it was necessary to give the trumpetconsiderable "lead" with reference to the rolls. In other words, as thetraverse occurs in one direction,

thoroughly practical solution for the problems presented by them. Statedmore specifically, the

invention provides a thoroughly reliable traversing mechanism forhandling a ribbon-sliver in a drawing mechanism 'of the type abovedescribed and in which the control of the edge fibers-is maintainedpractically as effectively as though the traversing motion were notused, which can be manufactured economically, and which. will require aminimum of care and attention in operation.

6 The nature of the invention will be readily; understood from thefollowing description when parts shown at the lus'trated in Fig.3 andthe parts immediately connected therewith; a

Figs. Sand 6 are sectional views, with parts in elevation, showingdetails of the traversing mechanism;

Fig. 7 is a diagrammatic, sectional view, on a larger scale, of thedrawing mechanism shown in Figs. 1 and 2;

Fig. his a rear elevation of the folding roll illustrated in '1, showingthe manner in which the silver is fed to them;

9 is a pe spective view of a portion of a sliver illustrating certain ofthe effects of the operations which it-goes through; and

Fig.10 is a transverse, sectional view of the folded sliver.

Referring first to Fig. 7, it will-be observed that thedrawing mechanismthere shown comprises upper anddower rear rolls l-and 3, respectively, asecond or intermediate pair of rolls 4 and I,

particularly of said rolls.

upper and lower folding rolls 6 and 1, and upper and lower front rolls 8and 9. The bottom rolls may be driven in the usual manner and thefolding rolls are positively connected together through the gears 6a.and 10,, Fig. 1. Immediately behind the first pair of rolls 2 and 3 is atrumpet In for guiding the sliver S into the bite The second pair ofrolls 4 and 5 revolve at a higher peripheral speed than the rear rolls 2and 3 in order to give the desired draft, and for the same reason thefront rolls 8 and 9 revolve at a higher peripheral speed than do thefolding rolls 6 and]. Usually, however, a. minimum draft occurs-betweenthe second pair of rolls and the folding rolls, the latter rolls runningat'a slightly higher peripheral speed, in order to pull the sliver intothe folding roll definitely and under the desired control. This step inthe feed of the sliver is utilized solely to perform the .foldingoperation. Thus the drawing operation is divided into two steps and thefold is produced between these steps.

In the usual arrangement, all of the lower rolls aredriven positively bygearing located at one end of the drawing frame, and the upper rolls arerevolved solely due to their contact with their respective 'lower rolls,these upper rolls being made in sections which are removably supportedfor convenience in threading up, cleaning, and the like. The lower rollsmay be either fluted or smooth, but the upper rolls customarily aresmooth. Usually the upper rolls 2, 4 and 8 are covered, and saddles andweights are used with them to hold them downwardly against theirrespective lower rolls with the desired degree of pressure. As shown inFig. 8, the upper folding roll preferably is grooved, while the lowerroll I is made sufficiently thin to fit into the groove of the upperroll with only the clearance necessary for smooth running. It isdesirable, also, to locate the two front pairs of rolls at a lower levelthan the two rear pairs in order to facilitate the folding operation. Asa rule, the upper roll 6 is self-weighted.

The arrangement above described is know and has been used heretofore. Ina drawing frame a series of units like that shown in Fig; 7 are arrangedside by side with the lower rolls running from one end to the other ofthe frame and common to all the units, as illustrated in Figs. 1 and 3.

As above stated, it is desirable to traverse the sliver, and for thispurpose. it is necessary to traverse both the folding rolls and thetrumpet.

I have found that the difficulties above discussedin performing thisoperation can be avoided, and

the necessity for lead of the trumpet traverse eliminated by traversingboth the trumpet and the folding roll in unison, but at a very low rate.In other words, if this rate is made slow enough, then any necessity forlead is completely avoided. The desirable condition is to make the speedof traverse as fast as possible while maintaining the movement of thesliver from the trumpet to its cooperating pair of folding rolls insubstantially a straight line lying at right.

plete reciprocation in, say, four minutes to one in twice that period.While the latter limit can be greatly increased, there is always thedanger of grooving the covered rolls if the sliver rests in one placelongv enough to overcome the elastic limit of the covering. Inasmuch asit is usually more convenient to drive the traversing mechanism from thelower rear roll 3 than from any other roll, and since the front rollspeed necessarily is determined by the spindle speed while the back rollspeed is varied to suit the requirements of the draft, it necessarilyfollows that the speed of this rear roll will vary greatly withdifferent conditions. Consequently, the time occupied in making acomplete traverse will vary.

A further condition encountered in traversing the folding rolls is thatthe upper roll is made up of disconnected sections so that it isimpractical. to traverse this roll directly. The lower folding roll,however, extends from one end to the other of the machine, although itmay also be made of sections secured together, end to end.

1 have found, however, that it is entirely prac-.

tical and greatly simplifies the traversing mechanism to traverse theupper roll through its engagement with the lower roll. In other words,if the lower folding roll is reciprocated longi- .tudinally of its ownaxis, the upper folding roll will be compelled to move 'with it becauseof the nature of its engagement with the lower roll. However, therenecessarily is some clearance between the opposite sides of the thinlower folding roll and the walls of the groove in its upper roll.Consequently, when the lower roll is being traversed rapidly in onedirection, it crowds against one wall of said groove and all of theclearance is between its opposite side and the adjacent wall. There is atendency for fibers to work into the crease or crevice so provided, andthus to produce a fuzzy edge on the folded sliver. The slow rate oftraverse above described, however, not only avoids the problem of lead,

but also makes it possible to produce the traverse sliver than therewould be if the traversing movement were absent.- Thus this slowtraverse solves two problems which have been exceedingly troublesome ina drawing mechanism of this type. At the same time it permits the use ofa single traversing mechanism to operate both the trumpets a'nd thefolding rolls.

The mechanism at present preferred for producing this traversing motionis illustrated in Figs. 1 to 4*, inclusive. .Referring to them, it willbe seen that the trumpets ill for the entire series of units are rigidlysecured'to a bar 12 which is mounted toslide in a path parallel to, andimmediately beside, the lower rear roll 3. Its rightthe lower foldingroll shaft 1', and the upper ends of the two arms of this yoke areslotted to receive pins Ill-48, Fig. 3, projecting laterally from acollar 20 which is held between two thrust bearing members 2l2|, both ofwhich are secured to the end I of the lower folding roll shaft.- Thearrangement is such that the shaft and the bearin members 2l--2l canrotate freely relatively to the collar 20, but all of these parts aresecured together for movement axially of the shaft. The pivots lB-IB arein line with the pivot 22 which connects the lever It with the trumpetbar l2. Consequently, if the lever is rocked on its fulcrum I5, itwillmove both the bar l2 and the shaft 1' in a direction parallel to thedrawing rolls and in unison with each other.

For the purpose of imparting this movement to the members l2 and I atthe slow rate desired, an eccentric strap 24 is pivoted to the lever Mat 25, this strap running on an eccentric 26 secured rigidly, butadjustably, to the shaft 21. A worm wheel 28, also fast on this shaft,is

' driven by a worm 3|! on a vertical shaft 3|, and

the latter is connected through worm gears 32 and 33 with the lowerreardrawing roll 3 which is driven by the usual gearing at the opposite endof the machine. Thus motion is transmitted positively from the roll 3 tothe trumpet bar l2 and the lower folding roll shaft 1', and results inreciprocating these members in unison at a very slow rate, as abovedescribed.

'The length of stroke of the reciprocating movement so imparted to theparts 1' and I2 can be conveniently adjusted by the arrangement shown inFigs. 4 and 6 forvarying the throw of the eccentric strap. As shown-insaid figures, the eccentric 35 is adjustably secured to the shaft 21 bya set screw 36 and this eccentric fits within an eccentric bushing 26,these two parts being secured together by a set screw 31 to form acompound eccentric unit. Several notches 38, Fig; 4, are .formed in theperiphery of the cocentric 35 to receive the point of the set screw 31,and numbers are associated with the respective notches to designate thelength of stroke that will be imparted to the trumpet rod and the lowerfolding roll by the relative adjustment of they gear (not shown) mesheswith a pinion 40 which preferably is integral with a bearing sleeve.Both these members ar splined to the shaft 1' and the sleeve is mountedto revolve in a bearing member 42 which is secured to any'convenientpart of the machine frame. Thus the shaft can slide freelylongitudinally of its own axis without disturbing itsrelationship to theparts that support and drive it.

Having thus described my invention, what I desire to claim as new is:

. 1. In a machine of the character described,.the combination of aseries of drawing uni-ts arranged side by side. each of said unitsincluding a plurality of pairs of drawing rolls arranged one in advanceof another to feed and draw asliver,

. each pair-including an upper roll and a lower roll,

a trumpet mounted in position to guide a sliver into the bite of therearmost pair of said rolls, another pair of rolls located betweenadjacent pairs of said feeding and drawing rolls for folding the sliveras it passes'from one of the latter pairs of rolls to the next, thelower rolls of said units being .common to the series and being driven,a bar on which the trumpets for said units rolls to traverse said barand said lower roll in unison.

2. In a machine of the character described, the combination of a seriesof drawing units arranged side by side, each of said units including aplurality of pairs of drawing rolls arranged one in advance of anotherto feed and draw a sliver,

each pair including an upper roll and a lower roll, a trumpet mounted inposition to guide a sliver into the bite of the rearmost pair of saidrolls, another pair of rolls locatedbetween adjacent pairs of saidfeeding and drawing rolls for folding the sliver as it passes from oneof the latter pairs of rolls to the next, the lower rolls of said unitsbeing common to the series and being driven, a bar on which thetrumpetsfor said units are secured, means supporting said bar forreciprocating motion in a direction parallel to said rolls, a levermounted at one end of said series of units, an eccentric strap connectedwith said lever to rock it, an eccentric for operating said strap. wormgearing driving said eccentric-

